Just make sure with bearings, if you answer is only two numbers like say 50 degrees, you need to add a 0 at the front so it's three numbers - 050 degrees, for example.
It's essentially the opposite of compound interest; instead of increasing in value, it decreases.
To calculate compound interest we do, for example 1000*1.1^2 - This will give us the value after 2 years at a rate of 10% compound interest
Now for deprecation we would do 1000*0.9^2 - This will give us the value after 2 years at a rate of deprecation at 10%. (It goes down by 10% of the current value per year)
Just remember with deprecation the decimal must be lower than 1.
Hayaa Just did this question.. The question was something like £800 depreciates by 30% in 2 years.